The present invention relates to an improved gage for measuring the length of mitered articles, especially inside and outside lengths of 45 degree miters. More particularly, it relates to such a gage for measuring and sizing mitered lengths for picture frames, windows and the like.
In the manufacture of picture frames, it is generally necessary to join together mitered lengths of frame stock, typically made of wood, metal or plastic or a composite thereof. Standard frames are square or rectangular and require four mitered lengths which form the four sides of the frame. These frame lengths must be accurately mitered to ensure proper sizing and fit of the subsequently joined lengths. The frame side lengths are typically cut with a double bladed miter saw. Mechanical gages have been employed to measure the lengths prior to cutting.
One commercial example of a mechanical gage is the VISI-MITER gage sold by Pistorius Machine Co., Inc., of Hauppauge, New York, covered by U.S. Design Pat. No. 224,717. The gage allows one to easily and without computations measure either inside, rabbet or outside "tip-to-tip" dimensions to suit the size of the item being framed. The gage includes a stainless steel gage strip having a scale comprised of etched and color-coded visual sighting lines which are parallel to the saw blade on the right hand side of the double miter saw. When material to be measured is placed on the stainless scale, the mitered face of the material is at right angles to the visual sighting lines. If the rabbet dimension is desired, the operator places the rabbet corner of the molding directly on the sighting line for the dimension desired. A stop is then placed against the miter and tightened with a handle. The operator can then repetitively cut accurate lengths of stock simply by placing the stock against the stop. For each change of size required, the above process must be repeated.
While quite satisfactory in use, the accuracy of the gage is limited by the visual accuracy of the operator, which can vary from piece to piece or operator to operator.